The weights of 4 boxes are 20, 40, 60 and 90 kilograms. Which of the following cannot be the total weight, in kilograms, of any combination of these boxes and in a combination a box can be used only once?
Shubham's mother is the sister-in-law of Shashi and Shashi is the only daughter of Parmeshwar. Ravi is Shubham's brother. How is Shashi related to Ravi?